Who has time to cook, measure portions and count each calorie? Frozen meals can help whittle your waistline. Which 10 brands offer the best bang for your buck… and your “bottom” line? Read on to find out. Plus, can you decode an ingredients list? Test your knowledge…

Heat-and-eat frozen entrées could be your ticket to a smaller pants size.

Research backs it up: A 2004 University of Illinois study found that women who ate portion-controlled entrées lost more weight and body fat over eight weeks than those who followed a self-selected diet identical in protein, fat, carbs and calories. Why? The latter group underestimated portions and calorie intake.

“Frozen entrées keep you from going overboard,” says Joy Bauer, a registered dietitian and author of the bestselling Joy’s LIFE Diet (Collins Living, 2008). “They’re especially great for individuals who don’t have a lot of time or hate cooking.”

Jill Weisenberger, Lifescript’s nutrition expert and a registered dietitian at Hampton Roads Center for Clinical Research in Norfolk, Va., agrees. “They remind you what a portion looks like, there are no leftovers to pick at and you can have them readily available at work and at home,” she says.

But not all frozen meals will help you lose weight, and supermarket freezer cases are stocked with hundreds of options.

Which should you choose? To make it easier, we evaluated 10 brands and some favorite dishes to find the best of the bunch.

PastaWhen you crave noodle-y comfort food, frozen pasta options abound at supermarkets. Which offer the best value and nutrition? Here’s what we found:

Stouffer’s is famous for its lasagna, so we picked up the vegetable version because it sounded healthful: “layered with a colorful medley of carrots, spinach, broccoli and onions.” More veggies and no meat means less calories, right? Think again.

Nestlé created Lean Cuisine to provide lower-calorie, lower-fat alternatives to its corporate sibling, Stouffer’s. Lean Cuisine offers a variety of dishes from six product lines: One Dish Favorites, Café Classics, Comfort Classics, Spa Cuisine Classics, Casual Eating and Dinnertime Selects. Entrées are usually 250 to 300 calories and never more than 400, making Lean Cuisine a safe diet bet.

Since the 1960s, Weight Watchers has been helping dieters lose weight without counting calories. Foods get a point value, allowing dieters to eat whatever they want within their daily allotment of points. To take the work out of dieting, Weight Watchers offers SmartOnes frozen entrées.

Tip:Low-cal doesn’t equal high nutrient. An easy fix for this dish? Add a generous side of steamed broccoli.

Best overall value for a mass-market brand:Marie Callender’s Grilled Chicken Alfredo Bake may have the most liberal portions for only 31¢ per ounce, but it’s also the most generous in calories, fat and sodium. For just a penny more per ounce, Weight Watchers SmartOnes Three Cheese Macaroni is more diet-friendly.

Best overall nutrition for a mass-market brand:It’s a tie between Weight Watchers SmartOnes Three Cheese Macaroni and Lean Cuisine’s Café Classics Grilled Chicken Caesar. Both lines have great nutritional profiles and a variety of healthy, diet-friendly products.

Organic PizzaWhen a food is labeled organic, it’s not so much about what goes in the meal as what doesn’t – like pesticides, chemical fertilizers, antibiotics and hormones. But an organic stamp on your frozen entrée doesn’t guarantee it’s low calorie.

“From a nutritional perspective, conventional frozen dinners can be just as healthful as organic meals,” Bauer says. “The nutritional profile of the meal trumps its organic status.”

But you’ll find plenty of highly nutritious organic fare out there – if you’re willing to spend a little more.

At first glance, O Organics Four Cheese Stone Baked Pizza seems like a smart choice. But look closer: It has two servings per container. One pizza packs 500 calories (250 each serving), 18 grams fat, 8 grams saturated fat and a 1,080 milligrams of sodium.

On the upside, it has 24 grams of protein and 4 grams of fiber, as well as 40% DV for calcium, 20% DV for vitamin C and 12% DV vitamin A.

Amy’s features organic, all-natural (no additives, preservatives or genetically modified organisms) vegetarian fare. It even offers three free diet plans online at Amys.com: The Amy’s Diet, Gluten-Free Diet and Vegan Diet. Meals for each plan are sold online and at supermarkets nationwide.

Cedarlane Natural Foods Inc. offers all-natural “made with organic” frozen foods. The company recently joined Barry Sears, Ph.D., to start a line of his Zone diet frozen foods, available at grocery stores or online (CedarlaneToGo.com).

Not all Cedarlane products are organic, so we chose the Mediterranean Stuffed Focaccia, which carries the Quality Assurance International organic certification. With spinach, mushrooms and three cheeses in a focaccia crust, this pizza-esque meal looks low-cal.

Best overall value for an organic brand: Cedarlane’s Mediterranean Stuffed Focaccia offers the biggest portion for 46¢ per ounce. Because you really shouldn’t eat more than half, you’re getting two servings per container. That’s a great value if you like leftovers.

Best overall nutrition for an organic brand:Cedarlane’s Mediterranean Stuffed Focaccia also has the fewest calories, fat and sodium per serving, although the saturated fat and sodium are the highest among the three. Just don’t eat the whole thing.

South-of-the-Border GourmetWhen you think “gourmet,” you don’t think “cheap.” Which is why we were happily surprised to find that two of the gourmet brands we chose were the least expensive – by far – among all 10 brands evaluated.

Founded in 1984 as an all-natural foods company, Kashi isn’t technically gourmet. But with such attention to quality, nutrition and flavor, we grouped them among the best. Kashi foods are high in fiber and protein. They’re sold at supermarkets and Whole Foods Market.

Its Black Bean Mango features black beans paired with roasted onions, peppers and carrots served over 7 Whole Grains Pilaf, finished off with a sauce of fire-roasted mango.

Best overall value for a gourmet brand: For 25¢ an ounce, Whole Foods’ and Trader Joe’s enchiladas tie for best value. You just can’t beat the price.

Best overall nutrition for a gourmet brand: Kashi’s Black Bean Mango may cost more than twice as much per ounce (which, by the way, is still cheaper than the organic brands), but it also has the most generous portion and more fiber, vitamin A and vitamin C than all 10 brands evaluated.